Suction cleaner with pneumatic filter cleaning means



Oct. 9, 1951 w. c. BELL ETAL SUCTION CLEANER WITH PNEUMATIC FILTER CLEANING MEANS 4 Sheets-Sheet 1 Filed July 17, 1947 MM 3. 0% WE W. C. BELL EI'AL Oct. 9, 1951 SUCTION CLEANER WITH PNEUMATIC FILTER CLEANING MEANS Filed July 17, 1947 4 Sheets-Sheet 2 I I l a! Oct. 9, 1951 w. c. BELL ETAL SUCTION CLEANER WITH PNEUMATIC FILTER CLEANING MEANS Filed July 17, 1947 4 sheeis-sheet 5 F/CiB.

1n enfor ZflzI/zam C Ee 5 Rag/ and 3658 By Swami A Home) Oct. 9, 1951 w. c. BELL EI'AL SUCTION CLEANER WITH PNEUMATIC FILTER CLEANING MEANS Filed July 17, 1947 4 Sheets-Sheet 4 Kay/770a A [for/my Patented Oct. 9, 1951 SUCTION CLEANER WITH PNEUMATIC FILTER CLEANING S William Charlton Bell, London, and Raymond Herbert Harold Press, Greenford, England, assignors to The Hoover Company, North Canton, Ohio, a corporation 01' Ohio Application July 17, 1941, Serial N6. 761,530 In Great Britain July 12, 1946 1 Section 1, Public Law 690, August 8, 1946 Patent expires July 12, 1966 7 Claims.

This invention relates to suction cleaners of the handle-propelled type comprising a casing containing a motor-driven fan and affording a main nozzle adapted to be maneuvered by means of a pivoted handle over the carpet or other surface to be cleaned for on-the-floor" cleaning. An agitator, preferably positively driven, is usually mounted within the main nozzle.

Many proposals have been made to provide a cleaner of the so-called closed circuit type having a mechanical separator or whirl chamber by which the heavier dirt particles are deposited in a dirt receptacle, and having no fabric or like dust bag through which the indrawn air is discharged, but these have not proved satisfactory in operation when applied to cleaners of the handle propelled type, possibly because some air containing light dust has always escaped from the casing into the atmosphere. Even when filter-covered outlet openings were provided for such dust-laden air no adequate means were included to maintain the filters in an efficient condition. The object of the present invention is to provide a suction cleaner of the handle-propelled type which will be free from the above disadvantages.

According to the present invention a suction cleaner of the handle-propelled type includes a preliminary separator or whirl chamber, a final filter chamber, a filter cleaning nozzle, movable relatively to the final filter surface for cleaning it, and conduits leading from the fan outlet to the final filter chamber, and from the filter-cleaning nozzle back to the preliminary separator or fan intake.

Conveniently the final filter is supported by, or in, the pivoted handle, for example, the handle structure may be hollow and include outlet openings covered by air-permeable fabric or the like, while the filter cleaning nozzle is arranged within the handle and provided with means for applying suction to it and means for moving it relatively to the inner surface of the filter material to remove the agglomerated dirt therefrom.

In one form of the invention the filter cleaning nozzle comprises a longitudinally extending mouth and projects from a tubular member mounted centrally within the handle and capable of rotation to traverse the mouth over the inner surface of the final filter. The filter-cleaning nozzle may thus comprise a tube of generally star-shaped cross section, for example having three projections equally spaced round the axis. one of the projections being slotted to provide a mouth and formed with rounded lips to ride over the surface of the filter material.

In some cases the suction cleaner may have means for applying suction to the filter-cleaning nozzle, and moving it relatively to the filter, while the main nozzle is in operation. The movement of the filter cleaning nozzle may be produced by the rocking movement of the handle as the suction cleaner is moved to and fro in use. for example the filter-cleaning nozzle may be arranged to be rotated step by step, as through ratchet mechanism, by the movements of the handle.

Alternatively, means may be provided for wholly or partially closing the main nozzle and applying suction to the filter cleaning nozzle when the filter is to be cleaned. In these cir cumstances a portion of the handle assembly, for example the handle grip, may be adapted to be moved relatively to the main portion of the handle so as to traverse the filter-cleaning nozzle over the surface of the filter.

The invention may be carried into effect in various ways, but certain constructions will be described by way of example with reference to the accompanying diagrammatic drawings, in which:

Figure 1 is a sectional side elevation showing the invention applied to a suction cleaner in which the fan has a vertical axis;

Figure 2 is a sectional plan view of the cleaner shown in Figure 1;

Figure 3 is a sectional plan on the line of 3-3 of Figure 1;

Figure 4 is a detail view showing the perforated handle tube;

Figure 5 is an enlarged diagram of the mechanism for rotating the filter-cleaning nozzle;

Figure 6 is a diagrammatic plan view showing the invention applied to a cleaner in which the fan has a horizontal transverse axis;

Figure 7 is a diagrammatic side elevation of the cleaner shown in Figure 6, and

Figure 8' is an enlarged detail diagram showing the mechanism for rotating the filter-cleaning nozzle in the arrangement of Figures 6 and 7.

In the arrangement shown in, Figures 1-5, the cleaner comprises a casing 10 mounted upon wheels I I and provided with a vertical axis motor driven fan l2.

The cleaner has a main nozzle l3 within which an agitator H is rotatably driven by a belt ll looping a pulley It at the lower end of the motor shaft.

These and other parts of the suction cleaner are similar to those of known constructions and will not be described in greater detail.

Below the fan is formed a whirl chamber, or

preliminary separator into which dust-laden air is drawn from the main nozzle by the suction of the fan in what may be termed a tangential direction, as indicated in Figure 2. The heavier dirt particles are flung against the outer walls of 5 the chamber so as to fall into a removable receptacle 2| constituting the base of the whirl chamber.

The lighter dust particles, which are not thrown down into the dirt receptacle, pass up- 19 permeable fabric, or like filtering material, 32

through which the air can pass into the atmosphere leaving the light dust particles on the inner wall of the fabric. As indicated in Figures 1 and 2, the interior of the handle communicates with the pressure side of the fan i2 through a 35 delivery passage 33 and pivotal Joint 33 which allows the handle to pivot up and down without breaking the communication between the delivery passage 33 and the interior of the handle.

The hollow handle contains a filter-cleaning go nozzle comprising a tube of generally triangular or three pointed starshaped cross section as. shown in Figure 3. Two of the points of the star merely rest on the inner surface of the handle in order to guide and locate the filter-cleaning nozg5 zle, whilst the third is formed as a slot ll with lips rounded as shown at 42 so as to ride smoothly over the surface of the fabric and constitute a nozzle mouth for cleaning it.

At its end nearer to the cleaner the filter-clean- 4o ing nozzle tube 40 is rotatable about a fixed tube 43 through which it communicates with a point on the suction side of the fan. For example it may communicate through an arcuate port 44 with a compartment 45 (Fig. 2) in the swivel joint 45 34 and thence through a passage way 45 with a port 41 (see in Figure 1) of the whirl chamber 20.

Accordingly the interior of the filter-cleaning nozzle is continuously in communication with the suction side of the fan and hence the area of the filter fabric between its lips is subjected to suction on its inside and atmospheric pressure on its outside, while the remaining fabric is subjected to atmospheric pressure on its outside and the delivery pressure of the fan on its inside. The

fine dust which fails to be trapped by the whirl chamber or preliminary separator 20 becomes agglomerated on the filter fabric 32 and hence when drawn back again into the whirl chamber 20 through the filter-cleaning nozzle 40 will be no deposited in the whirl chamber.

To enable the whole area of the filter to be cleaned the filter-cleaning nozzle is rotated relatively to the handle. This may be effected manually, for example by securing the outer end of the Q5 filter cleaning nozzle to the end grip ll of the handle which may be made rotatable relatively to the outer tube 30 of the handle.

It is however preferred that the rotation should be brought about automatically by the rocking 7o movement of the handle relatively to the casing as the cleaner is moved to and fro. One form of mechanism for achieving this is shown diagrammatically in Figure 5. In this arrangement a shaft 50 extends transversely through the fixed part of the handle tube and the fixed part of the filter-cleaning nomle tube 43. The rotating filtercleaning male 40 is formed at its inner end with a ratchet 5| which is engaged by a pawl 82 carried by an arm 53 rigid with the shaft 50. An arm 54 is rigid with one end of shaft ill and is connected by a link 55 to a pivot on a fixed part of the casing. The mechanism is so chosen that as the handle is oscillated up and down relatively to the casing the shaft 50 will be rocked to and fro and the pawl 52 on the arm 53 will advance the ratchet 5i and hence rotate the filter-cleaning nozzle with a step by step rotation. A second arm and pawl may, if desired, be provided on the 1| opposite side of the ratchet to produce a doubleacting effect, or alternatively a fixed pawl may be provided to prevent reverse rotation if friction is insufllcient to ensure this.

Figures 6-8 show a similar arrangement of filter-cleaning nozzle 66 as applied to a suction cleaner having a transverse horizontal fan and motor axis. In this arrangement the whole suction-creating unit including the motor and fan ii is arranged to turn with the handle relatively to the frame or chassis on which the casing of the cleaner is mounted.

This is a known type of cleaner which eliminates the need for a pivotal connection between the handle 65 and the casing or nozzle 66, although there is of course pivotal movement about the axis of the fan between the main nozzle 66 and chassis on the one hand and the motor, fan I and handle 65 on the other hand.

With such an arrangement the suction unit may turn relatively to the whirl chamber, the lower end of which is provided with a dirt receptacle having a detachable base. The fan ii is carried on the motor shaft adjacent to the whirl chamber whilst the belt for driving the agitator is conveniently driven by a pulley at the opposite end of the motor shaft from the fan and is housed in a passage remote from the conduit by which air is drawn into the whirl chamber by the main nozzle. In other respects th arrangement is generally analogous to that shown in Figures 1-5 except that the pivotal joint 34 provided in Figures 1-5 is not necessary in the construction of Figures 6-8. As in the previous construction separate passages 62 and .3 connect the interior of the handle with the pressure side of the fan ii and the interior of the filter-cleaning nozzle 84 with the whirl chamher.

As shown in Fig. 8 a ratchet wheel II is secured to the lower nd of the scavenger nozzle 64. Cooperating with the ratchet wheel I0 is a pawl 'il carried by an arm I! rigidly attached to a shaft 13. Also rigidly attached to the shaft 13 is an arm 14 to which is pivoted one end of a link 15 the other end of which is secured to a fixed part of the cleaner such as a part of the main nozzle 66. Thus, as in the first modification pivotal movement of the handle 65 in the normal operation of the cleaner will actuate arm 14 to intermittently reciprocate the pawl II and intermittently rotate the ratchet wheel II and scavenger nozzle N to clean the interior surface of the final filter.

It will be appreciated that the invention is not limited to the particular construction described by way of example and shown in the diagrammatic drawings. Thus for example the movement of the filter-cleaning nozzle may be produced manually and may be performed only intermittently at times when the main nozzle is not in operation. In these circumstances means may be provided for wholly or partially closing the main nozzle when the filter-cleaning nozzle is put into use. This is particularly conveniently effected in an arrangement such as that of Figures 6 and 7 in which the belt is arranged in a separate passage. Means may be provided to prevent the rotation of the nozzle unless and until the necessary adjustments have been made to ensure that the air circuit is arranged for air to fiow in the right direction. Moreover the form of the filter-cleaning nozzle may vary. Thus instead of a longitudinal slit or mouth it may be provided with an annular or circumferential mouth or a number of such mouths and may be arranged to be reciprocated longitudinally in order to enable such mouths to traverse the whole area of the filter. Again instead of a whirl chamber the preliminary separator may com- I prise a rotary member of known type by which the dirt particles are mechanically separated before the dust-laden air is discharged to the final filter.

What we claim as our invention and desire to secure by Letters Patent is:

1. A suction cleaner comprising, an ambulatory body, a nozzle carried by said body, a hollow handle for propelling said body over a surface to be cleaned, a motor driven fan, a passageway communicating between the suction side of said fan and said nozzle, said passageway including a preliminary dirt separator, a final dirt filter positioned within said handle and interiorly connected to the pressure side of said fan, a scavenger nozzle movably positioned against the inner surface of said final filter and interiorly connected to the suction side of said fan, a pivotal joint for pivotally connecting said handle to said body and means actuated by pivotal movement oi? said handle relative to 'said body for moving said scavenger nozzle over the interior surface of said final filter.

2. A suction cleaner comprising; an ambulatory body including a suction nozzle; a handle pivotally articulated to said body; a preliminary dirt separator associated with said body; a final dirt filter in said handle; a scavenger nozzle positioned to contact the inner surface of said filter; a motor-driven fan; conduits connecting said suction nozzle, preliminary dirt separator, fan,

final filter and scavenger nozzle; said fan and conduits being so connected as to move air through both of said nozzles through said preliminary dirt separator and then through said final filter and means actuated by pivotal movement of said handle for moving said scavenger nozzle over the inner surface of said final filter.

3. A suction cleaner according to claim 2 in which said handle includes a cylindrical casing, said final filter comprises a cylindrical filter within said casing and said scavenger nozzle comprises a tube of star-shaped cross-section in contact with the interior surface of said filter.

4. A suction cleaner according to claim 2 in which said handle includes a cylindrical casing, said filter comprising a cylindrical filter bag within said casing, said scavenger nozzle is rotatable on the interior of said filter bag and said moving means comprising a ratchet and pawl mechanism operated by the normal pivotal movement of said handle.

5. A suction cleaner comprising, an ambulatory body, a suction nozzle associated with said body, a handle pivoted to said body for moving said nozzle about over a surface to be cleaned, a filter carried by said handle, a scavenger nozzle movable over the surface of said filter, a fan, conduit means for connecting each of said nozzles to the suction side of said fan, a pivotal linkage mechanism connected between said handle and body and means actuated by said linkage mechanism upon pivotal movement of said handle relative to said body for moving said scavenger nozzle over the surface of said filter.

6. A suction cleaner according to claim 5 in which said handle comprises a foraminous hollow casing, said filter comprises a slotted tube in contact with the interior surface of said bag and said linkage actuated means comprising a ratchet and pawl mechanism for rotating said scavenger nozzle over the interior surface of said filter bag.

7. A suction cleaner according to claim 5 in which said linkage actuating mechanism comprises ratchet and pawl mechanism for moving said scavenger nozzle over the surface of said filter in a step by step movement.

WILLIAM CHARLTON BELL. RAYMOND HERBERT HAROLD PRESS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 22,336 Bible June 22, 1943 1,929,025 Leathers Oct. 3, 1933 1,954,416 Leathers Apr. 10, 1934 2,002,636 Leathers May 28, 1935 2,184,732 Brewer Dec. 26. 1939 2,287,921 White June 30, 1942 2,287,924 White June 30, 1942 

